Update google_cloudbuild_trigger documentation
Update google_cloudbuild_trigger documentation

* Order arguments alphabetically
* Add missing argument 'project'

ubschmidt2/terraform-provider-google,ubschmidt2/terraform-provider-google,hashicorp/terraform-provider-google-beta,hashicorp/terraform-provider-google-beta,drebes/terraform-provider-google,hashicorp/terraform-provider-google,terraform-providers/terraform-provider-google,drebes/terraform-provider-google,terraform-providers/terraform-provider-google,hashicorp/terraform-provider-google-beta,ubschmidt2/terraform-provider-google,hashicorp/terraform-provider-google,hashicorp/terraform-provider-google,terraform-providers/terraform-provider-google,hashicorp/terraform-provider-google,terraform-providers/terraform-provider-google,terraform-providers/terraform-provider-google,drebes/terraform-provider-google,ubschmidt2/terraform-provider-google,hashicorp/terraform-provider-google-beta,drebes/terraform-provider-google